Features of the transposon mutant strains.

1biofilm formation restored by adding of p-amino benzoic acid
2root colonization was performed in monoaxenic Lactuca sativa test system (see Materials and Methods and Fig. 2–4)
3mean value including standard deviation calculated from six independent experiments in absence (-Trp) and presence (+Trp) of tryptophan (see Materials and Methods).
Colonization and other features were indicated as present +; reduced (+), and absent -. ‘n.d.’ stands for not determined. PGP: plant growth promotion.

1. 添加对氨基苯甲酸（p-amino benzoic acid）可恢复生物膜（biofilm）的形成。
2. 根定殖实验采用单无菌莴苣（Lactuca sativa）测试系统进行（详见材料与方法及图2~4）。
3. 本研究中，色氨酸缺失（-Trp）与色氨酸存在（+Trp）两组条件下的6组独立实验所得数据用于计算均值及标准差（详见材料与方法）。
定殖能力及其他性状的标注规则如下："+"表示存在，"(+)"表示减弱，"-"表示缺失；"n.d."代表未测定（not determined）。PGP：植物生长促进（plant growth promotion）。